From the
Erowid Codeine FAQ:
The LD50 (lethal dose for %50) is 800mg in the average person. Death from codeine, unlike most opiates, includes restlessness, seizures and eventually death from respiratory arrest. Some sources indicate that the lower-end LD50 may be around 500mg, so doses above 450mg are in the red zone.
[Erowid Note: We believe the LD50 data listed above is based on a single paper which reported a human death at 12 mg/kg. Unfortunately the route of administration for this death was not listed. Without this information, the report is basically meaningless.
Estimating an LD50 in humans is nearly impossible as LD50 data cannot be directly interpreted between humans and other species. Known oral LD50s for codeine sulphate are: 430 mg/kg in rats and 395 mg/kg in mice. Oral LD50s for codeine phosphate include: 266 mg/kg in rats, 237 mg/kg in mice, and 100 mg/kg in rabbits. It should be remembered that a dose which can be easily tolerated by someone with a significate opiate tolerance could kill an individual with no tolerance.]
tablets / oral & sublingual)
